# CVE-2021-1271: Cisco Web Security Appliance Stored Cross-Site Scripting Vulnerability

> Authenticated attackers can inject malicious scripts into the Cisco WSA management interface, allowing arbitrary code execution in the victim's browser context.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 20 Jan 2021
- **Updated:** 12 Nov 2024
- **Also known as:** GHSA-xp9j-q8vg-2xqp

## What is CVE-2021-1271?

CVE-2021-1271 is a medium-severity cross-site scripting vulnerability in Cisco Web Security Appliance (WSA), published on 20 Jan 2021. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

A vulnerability in the web-based management interface of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to conduct a stored cross-site scripting (XSS) attack against a user of the interface of an affected device. The vulnerability exists because the web-based management interface does not properly validate user-supplied input. An attacker could exploit this vulnerability by inserting malicious data into a specific data field in an affected interface. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2021-1271?

It affects 1 product.


Products: Cisco Web Security Virtual Appliance.

## How do I fix CVE-2021-1271?

No fix has been published for CVE-2021-1271 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-1271 being exploited?

There is no known exploitation of CVE-2021-1271 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Web Security Appliance (WSA)

- [CVE-2015-6287](https://insights.sbomify.com/CVE-2015-6287/): Denial of service in n/a (medium 5.0)
- [CVE-2015-6290](https://insights.sbomify.com/CVE-2015-6290/): Denial of service in n/a (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-1271 and fix it if it is affected.

What it is: CVE-2021-1271 is a medium-severity cross-site scripting vulnerability in Cisco Web Security Appliance (WSA), published on 20 Jan 2021. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-1271 in the wild and no public exploit code.

Affected product: Cisco Web Security Appliance (WSA). No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2021-1271/ (Markdown: https://insights.sbomify.com/CVE-2021-1271/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-1271
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-1271
- OSV: https://osv.dev/vulnerability/CVE-2021-1271

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-1271/
Summaries are generated and may contain mistakes; the official description above is the record.